We wouldn't want to mess with Directioners, but it seems one writer has riled them up after signing a book deal to release her fan fiction.

Amateur writer Anna Todd released her first story, After, in 300 daily installments online and achieved more than 800million reads before Gallery Books offered her a six-figure advance to turn the stories into books, according to Billboard.

But One Direction fans are NOT happy and are now campaigning to stop the release by trending the hashtag '#stopannatodd' worldwide on Twitter, claiming she's not a fan and the stories could upset band members Harry Styles, Louis Tomlinson, Zayn Malik, Niall Horan and Liam Payne.

The 25-year-old writer, from Texas, uses Wattpad, an online writing community which is popular with readers of fan fiction and she's now set to release three volumes of her stories.

(Image: Getty)

Reports suggest the first book could be released in November and the rights for a movie has also been snapped up - meaning Anna could be about to make a LOT more money.

Her story tells the tale of an 18-year-old college student, Tessa Young, who lives a simple life, achieves excellent grades and is dating a "sweet" boy, until another boy turns her life upside down.

Tessa meets a bad boy named Harry (see what she did there), who has too many tattoos and piercings and shatters her plans for the future.

Anna insists she is a big fan of the band and simply had a "soft spot" for the 20 year old singer and him and Liam are her "babes", but fans of 1D claim the story makes Harry look like an "abusive" lover and it shouldn't be sold to young girls.